Man,with that space,you should get a HPS...40 W or bigger...you dont have to fuck around with ducting,inline fans,or other complicated bullshit..just hang the HPS..and point alot of fans up at the bulb...this will dissipitate the heat,and your plants will grow alot faster,and healthier than CFL's...look in ebay,there are some deals there.If not all you need is around $150 for a brand new,professional quality HPS..from HTG Supply...those plants are stretched..and eys youer setup looks like shit.
Im not being mean,but its the sad truth my friend.